Synchroscope



March 30, 1937. c. L. BENNETT SYNCHROSCOPE File d Spt. 6, 1932 6 Sheets-Sheet 1 Inventor 67/ L Fennel Z 6'2 flllorney March 30, 1937.

c. L. BENNETT 2,075,163

SYNCH'ROS COPE Filed Sept. 6, 1932 6 Sheets-Sheet 2 flllorney Inventor March 30, 1937? c. 1.. BENNETT SYNCHROSCOPE Filed Sept. 6, 1932 6 Sheets-Sheet 3 COL-Oz WSOZOk tutx h VIA-71 v Inventor 1 J15. Zen/7M1? I I v flllorney March so, 1937. C.-L. BENNETT 2,075,163

SYNCHROS COPE Filed Sept. 6, 1952 6 Sheets-Sheet 4 Invenlor March 30, 1937.

SYNCHROS COPE Filed Sept. 6, 1932 6 Sheets-Sheet 5 ENG H 5HlFT.O4 SHIFT.08 SHIFTJZ 5HlFT.I6 5H\FT.?O

TEST IUNIT zumTs 3UNIT5 4UNIT5 sum-rs SECON 2 s I I ,5;

I Invenlor KL. 2519122202? M flllomey c. L. BENNETT 2,075,163

March 30, 1937. c. L'. BENNETT SYNCHROSCOEE Filed Sept. 6, 1952 6 Sheets-Sheet 6 Inventor (YZ. fiezzzzeii' By w /I Home y Patented Mar. 30, 1937 U N l T 1:1. D S T S OFFICE SYNCHROSCOPE Application September 6, 1932, Serial No. 631,947

8 Claims.

My invention relates to measuring instruments and particularly to measuring instruments employing principles of operation similar to those of the stroboscope, and an important object of my 5 invention is to employ such principles of action in structure of new and novel form, for measuring the duration of and estimating the number of vibratory, rotary, or combination movements of elements which have a periodic or cyclic movel ment.

It is an important object of my invention to provide a machine or apparatus for measuring the duration distance and recurrence of such periodic or cyclic movements or portions thereof and to adapt such machine or apparatus to such work as the timing and checking of machines such as watches, clocks, and the like so as to enable accurately determining constants in the relationship between the distance covered and the time consumed in the movement of elements thereof, so as to enable adjusting such movements or reconstruction of the elements to move in the desired relationship to the constant which isthe time-displacement ratio for the particular movement examined.

It is also an important object of my invention to provide an apparatus for carrying out the process described, wherein a periodically recurring visual element is postulated as the norm for comparison with an arbitrarily chosen moving element in the machine to be examined.

Other objects and advantages of my invention will be apparent from a reading of the following description in connection with the drawings wherein for purposes of illustration, I have shown preferred embodiments of my invention.

In the drawings:

Figure 1 is a transverse vertical section view through the watch or clock support.

Figure 2 is a side elevation view of Figure 1, taken from the right.

Figure 3 is a top plan view of the commutator structure.

J Figure 4 is a vertical longitudinal section view through the commutator structure.

Figure 5 is a top plan View of Figure 1.

Figure 6 is a diagram of the relationship and electrical connections between the various elements of the embodiment.

Figure '7 is a perspective view of one of the commutator brushes.

Figure 8 is a view of a chart showing constants for the calculation of variations from accuracy of the movement of a watch balance-wheel.

Figure 9 is a bottom plan view of the brush carrier or rotor of the commutator structure shown in Figure 3.

Figure 10 is a horizontal sectional view showing in top plan the commutator.

Figure 11 is a transverse vertical sectional View taken through Figure 3 approximately on' the line I l I and looking in the direction of the arrows.

Figure 12 is a transverse vertical sectional view through the brush carrier rotor and one of the brush holders showing the construction of one of the brush holders and the relation of the brush to the commutator.

Figure 13 is a top plan view of a modified form of commutator structure. 4 V

Figure 14 is a longitudinal vertical sectional view through a portion of 13.

Figure 15 is a similar sectional view through one of the individual spring contact holders shown in Figure 13.

Figure 16 is a top plan view of the post of one of said spring contact holders.

Since my invention comprises properly supporting the machine and the movement of a moving element which is to be measured and counted, such as a selected point on the balance wheel of a watch I provide the novel and efficient form of support illustrated in Figures 1 and 2 in the drawings, whereby the watch may be securely held and tested in any one of four or more positions, as it is the practice by manufacturers of high grade watches to do and the synchronized commutator structure for producing the visual recurring means of comparison conveniently located within reach of the person making the test so that manipulation thereof may be done easily and conveniently while visually comparing the movement of the selected point on the balance wheel of the watch with the flashes of a special type of lamp such as a neon lamp.

The flashing of the lamp is controlled by adjustment of the commutator structure, which is driven by means of a synchronous prime mover, such as a synchronous electric motor.

The watch support comprises a table 51 which has depending sides which are traversed by bolts 59a which clamp friction producing concaved washers 59 against washers 60 and against thearms of a U-shaped bracket 55 which the bolts 59a also traverse, the bracket 55 being secured by means of a screw or bolt 5! so as to be rotatable with a dial 56 which is secured upon one face of a disk 53 said dial having numbers thereon at selected points 53a for enabling proper designation of the positions which the table 51 and con- ,dicated at 68 in Figure 2. The table 51 is proseguently the watch secured thereon are made to assume while the tests are being conducted in the different positions; and the disk 53 is secured to a suitable support by means of a bracket 49.

' Below the table 5'! I mount a base 65 which has U-shaped arms traversed by a bolt 6| which also traverses arms 64' which are disposed between the arms'of the bracket 65 and secured to the mirror 63. A washer 61 and-a thumb nut 62 disposed on one end of the bolt 6| provide means for tightening the mirror 63 against rocking on the bolt 6| and in any desired adjusted position. The mirror 63 is provided for reflecting into the line of vision of the operator the. movements of the selected point on the balance wheel of the watch, when the watch is in an inverted position such as that invided with a suitable spring orfriction receptacle 58 which enables securing of a watch upon the table in a variety of positions in the plane of the table; h

The'preferred form of commutator structure is clearly illustrated in Figure 4, wherein'the letter T' generally designates a suitable table or platform which is provided at longitudinally spacedpoints withlongitudinal slots 24 and 25. In 1theslot24is placed a shaft 24a on the lower endvofwhich is a washer 28 engaging the bottom f h abl rand. s nn n the en 14, a wear washer. 28 thereunder and a nut '38 for 'drawinga portion, of larger diameter 21 into engagement withthe upper surface of the table in cooperation with thewasher 28 which engages the under-surface of the table, thereby enabling adjusting and locking theshaft 24a at any point of the length of the slot 24. Rotatably supported on the shaft. above, and by, the portion 21 is a toothed wheel or. pinion 5 and similarly disposed on the'shaft above the pinion 5 is a flywheel gov- ;ernor or balancer 26 which is pinned to the pinion 5 by the" screw 2611 which traverses the pinion 5 and passes upwardly into the flywheel 26 as shown in Figure jli j Below, the table T which is suitably supported, v.is a, synchronous electric motor shown in Figure 4,'whose shaft, 2 rises through an opening in the table and thereabove' and has on its upper end a-nut 3| and thewasher 32 clamping thereto alarge gear 3. which is meshed with the pinion 5 and also with the commutator pinion 4.

[The commutator pinion 4 is mounted on the enlarged lo'were'nd portion of a shaft |5which is -mountedin a slide block-22 which rests upon the table. T andhas depending bolts 22b passing throughtheslot 25 and engage d-with a'plate 22a 7 V which engages the underside of the table T.

Manipulation of I the bolts 2211 enables clamping of the block 22 in the desiredposition in the slot 25. The adjustability of the shaft 24a carrying the governor 26 and of the block 22. enables accommodation to be made for difierent sizes of pinions and gears, when the apparatus is used in connection with different periods and cycles.

imutatonrotor; 6which comprises a disk having mqu-nted thereon abroken ring I of dielectric material in the radial opening Ia of which, as

illustrated in Figure 10 and Figure 4 is placed an electrically conductive element 2|. As shown; the commutator'pla-te 6 is fastened with screws to the commutator gear 4. r

Mounted on the upper and reduced portion of the shaft |5 is the brush carrier or rotor 9 which comprisesa dielectric fdiskhaving a central open- ;Mounted-upon the commutator gear 4 is a com-.

ing receiving the reduced lower end portion of a knurled dielectric knob l2, the disk being fastened with screws to theknob as shown. For

normally urging the brush carrier toward the.

commutator'there is provided surrounding the reduced upper endportion of the shaft I5 a helical spring. l6 which is downwardly pressed by a washer 3 held in position by a split nut M which is adjustably anchored to the shaft I5.

The spring I6 is located in a recess in theupper part of the knurled knob l2 as shown in Figure 4.

, Arranged within the periphery of the brush carrier rotor 9 and circumferentially spaced are brush holders II which are numbered to 8 in the drawings, Figure 3. Each of the brush holders comprises a, bolt which passes upwardly through the brush carrier rotor 9 and hasa notched head on'its lower end which receives and holds a U-shaped brush wiper 8 illustrated in Figure '7. The upper end of the bolt is threaded and has threaded thereon a washer l0 and a the block 22 and a longitudinally movable rod H which traverses the standard l8 and is provided on'its outward end with a handle 28; An enlarged squared head or brake shoe |8a.-is on the inward end of the rod l9 and slides in a conformably shaped recess in the standard l8 wherein a coiled spring circumposed on the rod l9 acts between the inner end of: the recess and the head or brake shoe l8'a for pressing the brake shoe against the. outer edge of the brush carrier. or rotor 9. It will be obvious that the brake |8a is provided to prevent the rotation of the brush carrier or rotor 9-by the revolving commutator ring I and segment 2| until it becomes desirable to advance or retard the occurrence of the contact of the.

brushes 8 with the commutator segment 2| for the purpose of changing the incidence of the flashes with which the movements of the selected point on the balance wheel 'of the watch are to be visually compared.

' Contactof the brushes 8 with the segment 2| of the commutator and hence the occurrence of the flashes of the neon lamp is so adjusted by the means described as to be in step with the correct,

standard time swing for the balance arm-of the watch, clock, or other periodically revolving or reciprocating object which is being tested so as to enable observing whether or not the object is moving at the correct speed and beat period. The brushes 8 and the commutator segment 2| are arranged to close'an electrical circuit and cause the neon glow lamp, or an electric light to r V flash, also a relay for operating a'counter or other apparatus requiring more current to operate than is needed for the operation of the lamp. The duration of contact must not exceed the time it takes'an accurately swinging balance arm orlpendulum indicatoror any other observation indicator which may be selected, to move an amount equal to the width of the selected detection unit, such as the width at the out end of the balance arm, but can be less so that when the commutator segment 2| closes and breaks the circuit theneon light, electric light, and relay will the neon light.

be energized and deenergized in a period of time that will enable a clear observation of the detection unit or balance arm. This detection unit or balance arm will appear as stationary or as shifted according to its position while in motion and during the standard for periodical contacts of the brush 8 with the segment 2 I.

In a case of testing the speed of movement of other than revolving or reciprocating objects the closing of the circuit is arranged to take place at equal intervals of time so that the observation indicator on the moving object will show itself according to its velocity at a location proportional to the standard amount of movement when compared with the time duration of the test.

It is arranged that the object being tested will move in the same direction each time the circuit is closed by the commutator segment, except when a rearrangement is made in which closing of the circuit will occur for each direction of reciprocating motion. The latter arrangement is desirable when testing to locate the halfway point on the stroke and also for locating the end of the strokes, thereby making it possible to determine accurately the length of the swing and the end of the swing as well as the halfway location of the balance motion on a watch or pendulum or any other object having reciprocatory motion.

This is done by advancing or retarding the closings of the circuit so that the neon light is energized and flashes at a time when the balance arm or any other observation indicator appears stationary and clear with no apparent wavering Which would appear at any other energization of It is also possible to determine the end of the stroke of the observation indicator by causing the neon light to be flashed at a slightly faster or slower speed than that of the balance arm or pendulum. By this procedure a slowly shifting appearance of the balance arm or pendulum can be obtained in which the arm or pendulum appears to move toward one end of its stroke and then reverse itself and proceed slowly toward the opposite end of the stroke.

In the case of a watch, clock, or any other object with a balance arm, pendulum, or any other reciprocating or revolving object, it is advantageous to cause the neon light to flash at equal intervals of time so that the observation indicators on the moving objects will appear at approximately the same location while the object is moving in one direction only.

If the light flashes for each stroke go and come, the observed indicator will have a wavering appearance when the moving object under observation has a speed differing from that of the commutator and the neon light flashes which are considered standard.

One advantage of arranging a closing of the light circuit at every other stroke rather than at every stroke is'that a uniform reading appears even if the object under test is moving at a speed differing some from that of the standard. This enables comparison of my detection unit with any number of like units of which the observation indicator shows or can be estimated to have drifted to the right or to the left, whereby I compare the number of these units off in a standard unit of time.

By reason of the uniformity of reciprocating motion on watch balances a table, Figure 8, is

calculated out so as to show the number of seconds off as accumulated in a twenty-four hour period. The table being calculated on the basis of a comparison of a unit'of displacement within a unit of time, thereby making it possible to measure the velocity in various units of measure.

The effect of the weighted flywheel governor 26 which is attached to the pinion 5 and receives its motion from gear 3 is to impart steadier and smoother running to the commutator segment 2 l The slots 2 5 and 25 in the table supporting the commutator mechanism and the governor enable adjusting the gears and substitution of gears which are reqinred to drive the commutator at the speed desired.

The commutator brake [8a is arranged to hold the commutator brush carrier 9 and brushes 8 stationary so that the synchroscope reading can accumulate. The brake may be released temporarily from engagement with the brush carrier or rotor 9 to enable turning the rotor 9 by means of the knurled knob [2 in order to advance or retard the engagement of the brushes 8 with the commutator segment 2i, thus enabling a person to tell if the swing or stroke which said person is watching is coming from the right or from the left hand direction. This is accomplished by noticing the direction of the drift of the observation indicator on the object under test and then comparing the direction in which the commutator is revolving with the direction in which the brush carrier or rotor 9 was turned by hand, and the direction in which the observation indicator appears to have shifted. By means of the described manipulation it is also possible to tell if the object under test is running faster or slower than the standard speed, by noticing whether the observation indicator appears sooner or later in its swing.

The adjustable brush carrier or rotor S and the brushes are insulated from each other and so placed that in the event of either an advance or a retard adjustment of the rotor 9 for the purpose of closing the circuit to energize the neon light and a relay earlier or later than normal, that a better location for watching the observation indicator can be obtained and that it may be readily determined which way the swing of the balance arm or any other reciprocating member having an observation indicator, may be moving. This adjustable brush carrier or rotor 9 will enable a person to tell if the moving object under test is running fast or slow, by comparing the directions of rotation of the commutator segment 2i with the direction of drift of the observation indicator. If the commutator is rotating clockwise and the observation indicator on the moving object under test is observed to drift toward the right or clockwise, then by turning the knob l2 toward the right or clockwise the balance arm or any other observation indicator is caused to appear farther to the right of its originally observed position, then the apparent running drift of the observation indicator to the right indicates the object is running fast because it is gaining on the direction of stroke. If the rotor 9 is turned toward the left or counterclockwise, then the light will flash sooner than normal and the observation indicator will appear as shifted toward the left of the originally observed position, thereby indicating that the observation indicator on the moving object will be observed at constant intervals of time moving toward the right.

By using either of the foregoing procedures the observer can tell the direction of motion of the object under test and can determine if the object is moving faster or slower than the standard velocity. For example, if the object being tested is found drifting slowly clockwise or toward theright and the commutator ,2l is rotating clockwise and in the direction of movement of the observationindicator, it proves that the observation indicator is moving faster than the commuj 'tator cycle and the period of light flashes which is the indicator of the standard by which the movement of the observation indicator is being compared. If in the foregoing test the direction of drift of the observation indicator has appeared to be toward the left insteadof toward the right, it would have indicated that the object was moving slower than the commutator cycle, and hence slower than the standard velocity.

The relay operated counter 46 is provided to record the number of circuit closings taking place during the tests. VThe balance arm on most watches swings in one direction 2 times per second or 150 times per minute. Therefore, at

the end of 150 counts on the counter it is necessary to estimate. the distance that 'the balance arm drifted during the test. From this it is possible by reference to a table, such as that shown in Figure 8, to tell how close in seconds of 7 standard time or any other units of measure, by which the balance arm of the watch or of any other revolving or reciprocating object which may be running withrespect to the standard 24 hours of time. A table can be made to show the results in seconds per day, revolutions per minute, or in any other suitable units of measure.

- The binding nut i4 is located on shaft l5 and is for adjusting the spring 16 so as to press the commutator brushes 8 against the commutator disk 7? so that the commutator may run as.

smoothly as possible and make a good contact for closing the light circuit. 7

The multiple point switch 39 has its points connected with brush'holders I through 8 so that by selective setting of the switch 39 which may be located at a remote place from the commutator and motor, any desired adjustment of the inci-- dence of the closing of the circuit to energize the neon light earlier or later with respect to the position of the observation indicator on the object being tested may be made.

It is hereby possible'to achieve at a distance from the commutator an effect which is similar to that obtainable by manually adjusting the disk 9 by means of the knob I2. This adjustment of the incidence of the closing of the circuitis desirable to cause the light to flash at a preferred position and at a time in which the observation indicator of the object may be viewed, and also to enable determining the direction of the stroke of the object under observation, and to assistv in determining whether the movement of the object the spring friction washer 48 so thatthe dial 54 and the bracket 55 along with the adjustable table 51 and the watch adapter 58 can be turned on bolt 5| with some friction so that the dial 54 and the watch can be set at the desired angles at 75 which the time keeping ability of the watch or under observation is faster or slower than the 2,076,168 r V V clock or other time escapement is tested at for" position timing.

The adjustable table 51, enables the watch to be tested with the back of the watch up .as shown in the .top view at 56 also'the table 51 can be turned completely over so that'the watch can be timed with the backside of the watch down as indicated at 68.. To test a watch or an escape ment in the various perpendicular positions it is necessary to set the adjustable table 51 in the po sition shown at 51a with the flat sideof'the table and the back side of the" watch facing the front.

For testing a watch or an escapement in the front perpendicular and the various right and left an gular positions, the fixture and dialiis turned to the position'desired.

The adjustable plain mirrororthe magnifying mirror 63 is set facing the back side of the watch or other reciprocating escapement to enable the operator to view the back side down of the watch-,; especially the balance arm and its action while the test is being made according'to the synchro ternating current such as 60 cycle current through the commutator to light the neon light,

the duration of the contact should be less than the time frequency of the alternating current used, so that when the motor is running at the constant predetermined speed the neon light will flash only on one of its poles and continue to flash on the same pole as long as the speed of the motor does not change. second for the duration of'contact. 7

It is possible to tell whether the motor is driving the commutator at the desired speed by' watching the light flash appear on the same pole in the neon or other gas ionizing tube for a period of time. The above holds true for all of the A. C. polarity alternations which happen to be in multiple of the frequency of contact of the commutator.

The relay is operated in the circuit with the neon light, its purpose is to control another circuit suitable for operating the mechanical or magnetic counter 46. The purpose of the counter is to serve as a check on the duration of the tests so that the length or theproportlonal amount of drift of the observation indicator when viewed. by the aid of the constant periodic flash of the neon or other light, which is focused on the object under test in a dark or semi-dark place, can

compared with'the duration of time it takes in drifting.

The factthat the commutator which controls. the neon light and the relay isrun with the synchronous motor, insures the constant periodic flashing of the neon light and operation of the counter in exact step with the neon light and the relay. One arrangement is to have the counter register a predetermined numberrof light flashes per minute.

In place of using the relay in the circuit with I havegused about 1/500 of 'a:

the neon or other form of light flashes to operate g the counter it is possible to use a direct cam. The counter may be thrown in by a clutch which is not shown, when the test is to begin and thrown 4 out when desired'or when a'p'redetermined stopping point is arrived at where an electric contact 1 can cause a signal light or a bell which is not shown to operate. In the case of the cam operated electric contact or the commutator contact it is only necessary to throw a switch on or off in the contact circuit to start or stop the counter.

An observation housing may be built to house the moving object under test in such a way as to adequately prevent most of the outside light from entering and neutralizing the effect of the neon light flashes on the object under test. Openings in the housing may be placed at a distance from the object to be tested so as to enable viewing the object under test and from different points of vantage.

Besides the adjustment for retard or advance of the incidence of the circuit closings which is available through manually rotating the rotor or brush holder 9, the individual brushes may be given angularities with respect to the radii of the brush holder rotor 9 and the commutator segment 2| so that by using the switch 40 the proper brush may be chosen to engage with the segment 21 sooner or later.

The double pole double throw switch H provides a means for choosing either the direct current or an alternating current for operating the neon tube or glow lamp through the commutator circuit.

An example of a watch timing calculation using my synchroscope: The inside dia. of the balance rim of the balance wheel in a watch equals .40.

The average one way swing or travel of the balance arm equals of a revolution. The detection unit of drift equals .04" and is the unit of motion based on the exact distance through which the balance arm at the outer end should travel in 24 hours of motion.

.40"=the inside dia. of the balance rim. 1256640 6875=: rev. or of the 1% turn or the go and come of the balance rim.) 1

04(8639400000=i (of the circumference of the 6 .40 dia. or 1 swing) 21, 5985=units per swing 5 swings per second of the balance arm. 107. 9925 If one detection unit equals .04 movement of the balance arm at the outer end of same and for any other observation indicator, that would 7 indicate the 1/9,330,552 part of 24 hours, or

the 1/6480th part of a minute or the 1 /108th part of a second.

6480)9,330,552 (1439.9 say 1440 units or 1 unitfor each minute in 24 hours.

If the synchroscope shows a one unit drift of .the balance arm for each of the minutes of the test, there being 1440 min. in the 24 hours, then the number of seconds 011 in a 24 hours run is found by dividing 1440 units which equals the' l08)1440(13.33=seconds off in a 24-hour run. The

synchroscope showing a 1 unit of drift in'l minute.

Ifthe ,synchroscope shows only 1 unit of drift after the 10 minutes of test, that would indicate: l3.33+10=1.333 seconds off in a 24 hour run.

Thus a table similar to the one shown in Fig per second or 5 swings counting both of the directions per second.

One second=108 Det. units.

One detection unit of .04" drift for eachmin- V ute in the 24 hours.

13.33 sec. off in the 24 hour run if the synchroscope shows 1 unit off in a 1 min. test.

The table in Figure 8 is for use in conjunction withmy'syn'chroscope for the timing of revolving and reciprocating motions; Most of the watches have a balance arm swing of approximately Detection units in each sec. -g

revolution each way, or 1% rev. per cycle.

If the watch has a swing of A; to rev. more or less it will not change the reading on the table shown in Figure 8, a great deal. I have tested watches that ran with accuracy within second a day and which had a .40" inside dia. of the balance rim or at the position of the observation indicator, and will say that it took about 20 minutes to notice a drift of the balance arm or the observation indicator of .04", thus by ref-' erence to the table Figure 8 it shows-that the watch was running within second of accuracy irr what would ,be equivalent to 24;hours;of continuous running. 7

For determining fast or slow, and the exact frequency of the swing of the balanceof any 'escapement controlled by a regularcproceed' as follows: a V I Cause the neon light or other light means to flash at the desired standard intervals of time upona revolving or reciprocating object such as a balance arm and ring, so that the observation indicator on the balance arm, ring, pendulum or other moving object may be observed in a dark or semi-dark place with the observation indicator moving in the same direction for eachstandard flash.

This offers the preferable methodof telling the fast or slow and will aid in correcting the time motions of the observation indicator on the balance arm, ring, and hair sp'ringfofa watch or clock or on any other reciprocating escapement that has the regulator arm or an adjustable T means for controlling the balance and the hairspri-ng reciprocating periods.

After'noticing the positionof the observation indicator on the balance or pendulum while under '{testinmy .synchroscope machine, the regulator "of the watch or the .likeis moved in thefast or the slow direction which is marked or known on the watches andclocks and similarly regulated escapements. A sudden shift of the observation indicator, the balance run or the pendulum will be noticed.- If the regulator is moved 'to the fast or the slow and after having'pieviously noticed the gradual drifting direction of the observation indicator the balance arm or the pendulum, it can be seen that if. both of the motions, thedirection of the error drift of the balancearm or other observation indicator and the direction of the sudden shiftof the observation indicator was caused by moving the regulator, and took placein the same directionyas the motion which is being tested and is therefore indicatedas fast orslow according to whether or not the regulator was moved to the fast or the slow.

It is possible to shift the regulator of the watch or the like to a position in which the balance arm or a pendulum, .while'in motion under thegsym 'chroscope flashes will apparently appear at',a standstill for a minute or more according to the accuracy of same. The degree of accuracy can be determined by comparing the amount of drift in units of the observation indicator in a definite duration of test thus indicating the amount of error in units for the length of time tested and by referring to the table Figure 8, the operator is enabledto ascertain the amount in seconds that watch .iw ill run off in 24 hours. This information willena'ble' a watch expert to intelligently adjust the balance. hairaspring or. any of the .60

other, time controlling parts which are in the watchor clock or in any'other escapement so as to permit the regulator to be set at the central or the intermediate position, which is half way between the ffast and the slow? or at any other desired location. With my device itiis possible to checkthe extreme'faccura cy required ofmoving and reciprocating objectsby the Bureau of Standards at Washington, D. C. and for others elsewhere. r In Figure 13 is shown an alternative form of the commutator structure, which; instead of the brush rotor 9 and 'its appurtenances, is provided with a stationary. table in the form of a plate 100 which is rigidly mounted by blocks llll traversed byboltsor the likelil! tovthe table I03. The

which base. portion of larger diameter I05 resturged by a screw 101' into 'engagemen'twiththe;

of the invention the brushes or contact'elements ing against the uppersurface of the table 103 and cooperating with;a-;.washer I06 .whichis under face of the table 103. *Inthi'sembodiment are stationary, whereas in the embodiment described above, the contacts orbrushes are of the T rotary typ'e, that. is they are carriedso as to, be.

capable of being manually rotated relative to the commutator. In'the embodiment now, being described the shaft I M carries the pinion Hi8 which correspondsin action andfunction and position to the pinion 4,- of the first described embodi-J ment of the invention. The pinion I08 rotates relative to'the shaft 104, and carries around the shafta drum type commutator l09-which comprises a cylindrical block I III of in s ulatingmaterial and a metallic contact portion, Ill. 7 Mountedin the table I00 and surrounding the slottedas indicatedat I M from its, upper end. "The bolt passes through the table I 00. A threaded bushingl I5 is, engaged on the bolt l cl3'above and in engagement'with the upper surface of the table, while a nut H6 and a lock nut H! are on the lower end of-the nut below and engaging the undersurfac'e' of the table for clampingthe bolt in adjusted position."

'I'hreaded upon the upper 'end of the bolt I I3 .is'a knurled clamping knob 418 which" clamps commutator I09 is a plurality, of'spring. contact holders H2 corresponding inposition andnu'm a spring rod H9 located in 'theslot lM aga'i-nst the upper end portiori of the bushing 5 for clamping the spring contact rod in the desired? position of adjustment. The radially inward end portions of the spring contact rods H9. are deflected as shown 'in' Figure Bend are engaged with the commutator 109 in an evident manner.

The pinion I08 is driven by a large intermediate gear corresponding to the gear 3 of the first described embodiment, and the large'intermedi- "ategear is driven by virtueof its mounting upon the shaft of the prime mover of synchronous type, and the large intermediate gear is also in mesh with the pinionwhich carries the flywheel for regulating and smoothing the operation of the by assuring uniform rotation thereof.

Although I have shown and described herein preferred embodiments of the invention, it is to be definitely understood that I do not desire to gears and consequently of the commutator, there-.

limit the application of the invention thereto, and i l anychange or'changesmay be made in material 1 and structureand arrangement of parts; within the spirit of the invention and the scope of the subjoined claims. I

What is claimed is:

1. An apparatusfor testing the ment of a selected point on the balance wheel or other periodically or cyclically moving part of a watch or the like, said apparatusv comprising a timedisplacesupport, a synchronous prime mover mounted in conjunction with the support, flywheel governor means on the support, commutator means on'the support, a mutual connection between the synchronous prime mover] and the flywheel governor and thecommutator means, wherebythe commutator means is driven at a uniform predetermined rate, a rotatable brush rotor, a plurality of circumferentially. spaced brushes carried by the rotor for contact with the commutator, and

brake means carried by the support for engagement with the brush rotor for preventing .rotation of the rotor by the commutator, whereby to retain said brush rotor in a position of rotation in which the incidence of the brushes with respect to the electrical circuit completing means carried by the commutator is either retarded or advanced.

2. An apparatus for testing the time-displacement of a selected point on the balance wheel or other periodically or cyclically moving part of a watch or the like, said apparatus comprising a support, a synchronous prime mover mounted in conjunction with the support, flywheel governor means on the support, commutator means on the support, a mutual connection between the synchronous prime mover and the flywheel governor and the commutator means, whereby the commutator means is driven at a uniform predetermined rate, a rotatable brush rotor, a plurality oi circumferentially spaced brushes carried by the rotor for contact with the commutator, brake means carried by the support for engagement with the brush rotor for preventing rotation of the brush rotor by the commutator whereby to retain said brush rotor in a position of rotation in which the incidence of the brushes with the electrical circuit completing means carried by the commutator is either retarded or advanced, an electric circuit having conductors connected individually to said brushes, a multiple switch connected to said conductors, relay means and incidence counting means connected to the arm of said switch, andelectrical light means having one side connected to said relay means, the remaining side of said electrical light means being connected to a power circuit in which said synchronous prime mover is connected, said power circuit being also connected to the electrical connection element of the commutator, whereby operation of said electrical light means is synchronized with the rotation of the prime mover, so as to establish a visual norm in the form of periodic flashes for visual comparison with the incidence of the selected point on the balance wheel or other moving part of the Watch or the like.

3. An apparatus for testing the time-displacement of a selected point on the balance wheel or other'periodically or cyclically moving part of a watch or the like, said apparatus comprising a support, a synchronous prime mover mounted in conjunction with the support, flywheel governor means on the support, commutator means on the support, a mutual connection between the synchronous prime mover and the flywheel governor and the commutator means, whereby the commutator means is driven at a uniform predetermined rate, a rotatably adjustable brush rotor, a plurality of circumferentially spaced brushes carried by the rotor for contact with the commutator, brake means carried by the support for engagement with the brush rotor to prevent the same from being rotated by the commutator, so as to cause said brush rotor to hold a retarded or advanced adjustment of the incidence of the brushes with the electrical circuit completing means carried by the commutator, an electric circuit having conductors connected individually to said brushes, a multiple switch connected to said conductors, relay means and incidence counting means connected to the arm of said switch, electrical light means having one side connected to said relay means, the remaining side of said electrical light means being connected to a power circuit in which said synchronous prime mover is connected, said power circuit being also connected to the electrical connection element of the commutator, whereby operation 1 movement of the selected point of the watch balance wheel, so as to enable visually determining whether the balance wheel movement is lagging behind or is advancing ahead of the flashes of the light means indicating the norm of the movement for the balance wheel.

4. An apparatus of the character described comprising a synchronous motor, a rotatable commutator driven thereby including contact segment means, a rotatably adjustable brush holder having a plurality of equaily circumferentially spaced brushes thereon, said brush holder being supported so that the circle of said brushes is concentric with the axis of said commutator and said brushes may engage said segment means when said commutator is rotated by said motor relative to said brush holder, and releasable brake means supported adjacent to said brush holder and normally engaging said brush holder and preventing said brush holder from being rotated by reason of the engagement of its brushes with said rotatable commutator, the engagement of said brake normally preventing rotation of said brush holder in either direction from an adjusted position.

I 5. An apparatus of the character described comprising a synchronous motor, a rotatable commutator driven thereby including contact segment means, a rotatably adjustable brush holder having a plurality of equally circumierentially spaced brushes thereon, said brush holder being supported so that the circle of said brushes is concentric with the axis of said commutator and said brushes may engage said segment means when said commutator is rotated by said motor relative to said brush holder, and releasable brake means supported adjacent to said brush holder and normally engaging said brush holder and preventing said brush holder from being rotated by reason of the engagement of its brushes with said rotatable commutator, the engagement of said brake normally preventing rotation of said brush holder in either direction from an adjusted position, each of said brushes being normally aligned with a diameter of said brush holder and adjustable to engage and leave said segment means at different angles.

6. An apparatus of the character described comprising a synchronous motor, a rotatable commutator driven thereby including contact segment means, a rotatably adjustable brush holder having a plurality of equally circumferentially spaced brushes thereon, said brush holder being supported so that the circle of said brushes is concentric with the axis of said commutator and said brushes may engage said segment means when said commutator is rotated by said motor relative to said brush holder, and releasable brake means supported adjacent to said brush holder and normally engaging said brush holder and preventing said brush holder' from being rotated by reason of the engagement of its brushes with said rotatable commutator;

, the engagement of said brake normally preventing rotation of said brush holder, in either direction from' an adjusted position, and manual means for rotatably adjusting said brush rotor i relative to said'commutator.

"7. An apparatus of the character described 7 comprising a synchronous 'motor, a rotatable commutator driven thereby including contact segment means, a rotatably adjustable brush holder having a plurality of equally circumferentially spaced brushes thereon, said brush holder being supported so that the circle of, said brushes is concentric with the axis ofsaid'commutator and said brushes may engage paid mg I ment means when saidv commutator is rotated by said motor relative to said brush holder, and releasable brakemeans supported adjacent to said brush holder and normally engaging said brush holder and preventing'said brush holder from being rotated by reason of the engagement of its brushes withsaid rotatable commutator,i

the engagement of said brake normally preventing rotation of said brush holder in either direction from an adjusted position, and an electrical circuit including said motor, said brushes, a lamp, and remote switch means having a multiplicity of points to each one of which one of said brushes is' connected, said switch being operable to predetermine retarded, advanced, or coincident incidence of the energization of the said lamp by engagement of said brushes with said segment means.

8. An apparatus ofthe character "described comprising a synchronous motor, a rotatable commutator driven thereby including contact segment means, a rotatably' adjustable brush holder having a plurality of equally circum ierentially spaced brushes thereon,-said brush holder'being supported so that the circle of said brushes is concentric with the axis of said com-' mutator and said brushes may engage said segment means when said commutator is rotated,

by said motor relative to said brush holder," and releasable brake means supported adjacentto said brush holder and normally engaging said brush holder and preventing said brushholder from beingjrotated by reason of the engagement of its brushes with said rotatable commutator,

the engagement of said brake normally preventing rotation of said brush holder in either direction from an adjusted position, and an electrical energization by the engagement of said brushes withisaid segment means. 7

CLAUDE L. 

